(function (root,factory) {
  if (typeof define === 'function' && define.amd) {
    /*AMD. Register as an anonymous module.
    *define([], factory); */
    define([], factory());
  } else if (typeof module === 'object' && module.exports) {
    /*Node. Does not work with strict CommonJS, but
    // only CommonJS-like environments that support module.exports,
    // like Node.*/
    module.exports = factory();

  } else {
    /*Browser globals (root is window)*/
    root['watermark'] = factory();
  }
}(this, function () {

  function debounce(fn,opt, delay) {
    // 存储定时标识符，以便清除定时器
    let timer = null
    return function _debounce() {
      if (timer) clearTimeout(timer)
      timer = setTimeout(function(){
        fn(opt)
      }, delay)
    }
  }

  /*Just return a value to define the module export.*/
  var watermark = {};

  var defaultSettings={
    watermark_id: 'eye_wm_mask_wrap',          //水印总体的id
    watermark_prefix: 'eye_wm_mask_one',    //小水印的id前缀
    watermark_txt:"测试水印",             //水印的内容
    watermark_x:10,                     //水印起始位置x轴坐标
    watermark_y:10,                     //水印起始位置Y轴坐标
    watermark_rows:0,                   //水印行数
    watermark_cols:0,                   //水印列数
    watermark_x_space:60,              //水印x轴间隔
    watermark_y_space:60,               //水印y轴间隔
    watermark_font:'微软雅黑',           //水印字体
    watermark_color:'black',            //水印字体颜色
    watermark_fontsize:'18px',          //水印字体大小
    watermark_alpha:0.05,               //水印透明度，要求设置在大于等于0.005
    watermark_width:120,                //水印宽度
    watermark_height:120,               //水印长度
    watermark_angle:15,                 //水印倾斜度数
    watermark_parent_width:0,      //水印的总体宽度（默认值：body的scrollWidth和clientWidth的较大值）
    watermark_parent_height:0,     //水印的总体高度（默认值：body的scrollHeight和clientHeight的较大值）
    watermark_parent_node:null,     //水印插件挂载的父元素element,不输入则默认挂在body上
    monitor:true,                   //monitor 是否监控， true: 不可删除水印; false: 可删水印。
    htmlMode:true,                      //是否html模式，  true: 支持html; false: 纯文本。
  };

  var settingsToDefaultSetting = function (settings) {
    defaultSettings.watermark_id = settings.watermark_id || defaultSettings.watermark_id;
    defaultSettings.watermark_prefix = settings.watermark_prefix || defaultSettings.watermark_prefix;
    defaultSettings.watermark_txt = settings.watermark_txt || defaultSettings.watermark_txt;
    defaultSettings.watermark_x = settings.watermark_x || defaultSettings.watermark_x;
    defaultSettings.watermark_y = settings.watermark_y || defaultSettings.watermark_y;
    defaultSettings.watermark_rows = settings.watermark_rows || defaultSettings.watermark_rows;
    defaultSettings.watermark_cols = settings.watermark_cols || defaultSettings.watermark_cols;
    defaultSettings.watermark_x_space = settings.watermark_x_space || defaultSettings.watermark_x_space;
    defaultSettings.watermark_y_space = settings.watermark_y_space || defaultSettings.watermark_y_space;
    defaultSettings.watermark_font = settings.watermark_font || defaultSettings.watermark_font;
    defaultSettings.watermark_color = settings.watermark_color || defaultSettings.watermark_color;
    defaultSettings.watermark_fontsize = settings.watermark_fontsize || defaultSettings.watermark_fontsize;
    defaultSettings.watermark_alpha = settings.watermark_alpha || defaultSettings.watermark_alpha;
    defaultSettings.watermark_width = settings.watermark_width || defaultSettings.watermark_width;
    defaultSettings.watermark_height = settings.watermark_height || defaultSettings.watermark_height;
    defaultSettings.watermark_angle = settings.watermark_angle || defaultSettings.watermark_angle;
    defaultSettings.watermark_parent_width = settings.watermark_parent_width || defaultSettings.watermark_parent_width;
    defaultSettings.watermark_parent_height = settings.watermark_parent_height || defaultSettings.watermark_parent_height;
    defaultSettings.watermark_parent_node = settings.watermark_parent_node || defaultSettings.watermark_parent_node;
    defaultSettings.monitor = settings.monitor || defaultSettings.monitor;
  }


  /*加载水印*/
  var loadMark;
  loadMark = function (settings) {
    /*采用配置项替换默认值，作用类似jquery.extend*/
    if (arguments.length === 1 && typeof arguments[0] === "object") {
      var src = arguments[0] || {};
      for (key in src) {
        if (src[key] && defaultSettings[key] && src[key] === defaultSettings[key]) continue;
        /*veronic: resolution of watermark_angle=0 not in force*/
        else if (src[key] || src[key] === 0) defaultSettings[key] = src[key];
      }
    }

    settingsToDefaultSetting(settings);

    /*如果元素存在则移除*/
    var watermark_element = document.getElementById(defaultSettings.watermark_id);
    watermark_element && watermark_element.parentNode && watermark_element.parentNode.removeChild(watermark_element);

    /*如果设置水印挂载的父元素的id*/
    var watermark_parent_element = document.getElementById(defaultSettings.watermark_parent_node);
    var watermark_hook_element = watermark_parent_element ? watermark_parent_element : document.body;

    // console.log(watermark_hook_element, '0-0-0-0-0-')

    /*获取页面宽度*/
    var page_width = Math.max(watermark_hook_element.scrollWidth, watermark_hook_element.clientWidth);
    /*获取页面最大长度*/
    var page_height = Math.max($('html').height(),watermark_hook_element.scrollHeight, watermark_hook_element.clientHeight);

    var setting = arguments[0] || {};
    var parentEle = watermark_hook_element;

    var page_offsetTop = 0;
    var page_offsetLeft = 0;
    if (setting.watermark_parent_width || setting.watermark_parent_height) {
      /*指定父元素同时指定了宽或高*/
      if (parentEle) {
        page_offsetTop = parentEle.offsetTop || 0;
        page_offsetLeft = parentEle.offsetLeft || 0;
        defaultSettings.watermark_x = defaultSettings.watermark_x + page_offsetLeft;
        defaultSettings.watermark_y = defaultSettings.watermark_y + page_offsetTop;
      }
    } else {
      if (parentEle) {
        page_offsetTop = parentEle.offsetTop || 0;
        page_offsetLeft = parentEle.offsetLeft || 0;
      }
    }

    /*创建水印外壳div*/
    var otdiv = document.getElementById(defaultSettings.watermark_id);
    var shadowRoot = null;

    if (!otdiv) {
      otdiv = document.createElement('div');
      /*创建shadow dom*/
      otdiv.id = defaultSettings.watermark_id;
      otdiv.setAttribute('style', 'pointer-events: none !important; display: block !important');
      /*判断浏览器是否支持attachShadow方法*/
      if (typeof otdiv.attachShadow === 'function') {
        /* createShadowRoot Deprecated. Not for use in new websites. Use attachShadow*/
        shadowRoot = otdiv.attachShadow({mode: 'open'});
      } else {
        shadowRoot = otdiv;
      }
      /*将shadow dom随机插入body内的任意位置*/
      var nodeList = watermark_hook_element.children;
      var index = Math.floor(Math.random() * (nodeList.length - 1));
      if (nodeList[index]) {
        watermark_hook_element.insertBefore(otdiv, nodeList[index]);
      } else {
        watermark_hook_element.appendChild(otdiv);
      }
    } else if (otdiv.shadowRoot) {
      shadowRoot = otdiv.shadowRoot;
    }
    /*三种情况下会重新计算水印列数和x方向水印间隔：1、水印列数设置为0，2、水印宽度大于页面宽度，3、水印宽度小于于页面宽度*/
    defaultSettings.watermark_cols = parseInt((page_width - defaultSettings.watermark_x) / (defaultSettings.watermark_width + defaultSettings.watermark_x_space) || 0);
    var temp_watermark_x_space = parseInt((page_width - defaultSettings.watermark_x - defaultSettings.watermark_width * defaultSettings.watermark_cols) / (defaultSettings.watermark_cols));
    defaultSettings.watermark_x_space = temp_watermark_x_space ? defaultSettings.watermark_x_space : temp_watermark_x_space;
    var allWatermarkWidth;

    // console.log()

    /*三种情况下会重新计算水印行数和y方向水印间隔：1、水印行数设置为0，2、水印长度大于页面长度，3、水印长度小于于页面长度*/
    // console.log(page_height, 'a', defaultSettings.watermark_y, 'b', defaultSettings.watermark_height, 'c', defaultSettings.watermark_y_space, 'd');
    defaultSettings.watermark_rows = parseInt((page_height - defaultSettings.watermark_y) / (defaultSettings.watermark_height + defaultSettings.watermark_y_space) || 0) ;
    var temp_watermark_y_space = parseInt((page_height - defaultSettings.watermark_y - defaultSettings.watermark_height * defaultSettings.watermark_rows) / (defaultSettings.watermark_rows));
    defaultSettings.watermark_y_space = temp_watermark_y_space ? defaultSettings.watermark_y_space : temp_watermark_y_space;
    var allWatermarkHeight;

    if (watermark_parent_element) {
      allWatermarkWidth = defaultSettings.watermark_x + defaultSettings.watermark_width * defaultSettings.watermark_cols + defaultSettings.watermark_x_space * (defaultSettings.watermark_cols - 1);
      allWatermarkHeight = defaultSettings.watermark_y + defaultSettings.watermark_height * defaultSettings.watermark_rows + defaultSettings.watermark_y_space * (defaultSettings.watermark_rows - 1);
    } else {
      allWatermarkWidth = page_offsetLeft + defaultSettings.watermark_x + defaultSettings.watermark_width * defaultSettings.watermark_cols + defaultSettings.watermark_x_space * (defaultSettings.watermark_cols - 1);
      allWatermarkHeight = page_offsetTop + defaultSettings.watermark_y + defaultSettings.watermark_height * defaultSettings.watermark_rows + defaultSettings.watermark_y_space * (defaultSettings.watermark_rows - 1);
    }

    var x;
    var y;
    // console.log(defaultSettings.watermark_cols, '12121221212')
    // console.log(defaultSettings.watermark_rows, '67676767767')
    for (var i = 0; i < defaultSettings.watermark_rows; i++) {
      if (watermark_parent_element) {
        y = page_offsetTop + defaultSettings.watermark_y + (page_height - allWatermarkHeight) / 2 + (defaultSettings.watermark_y_space + defaultSettings.watermark_height) * i;
      } else {
        y = defaultSettings.watermark_y + (page_height - allWatermarkHeight) / 2 + (defaultSettings.watermark_y_space + defaultSettings.watermark_height) * i;
      }
      for (var j = 0; j < defaultSettings.watermark_cols; j++) {
        if (watermark_parent_element) {
          x = page_offsetLeft + defaultSettings.watermark_x + (page_width - allWatermarkWidth) / 2 + (defaultSettings.watermark_width + defaultSettings.watermark_x_space) * j;
        } else {
          x = defaultSettings.watermark_x + (page_width - allWatermarkWidth) / 2 + (defaultSettings.watermark_width + defaultSettings.watermark_x_space) * j;
        }
        var mask_div = document.createElement('div');
        if(defaultSettings.htmlMode){//html
          mask_div.innerHTML = defaultSettings.watermark_txt;
        }else{//text
          var oText = document.createTextNode(defaultSettings.watermark_txt);
          mask_div.appendChild(oText);
        }
        /*设置水印相关属性start*/
        mask_div.id = defaultSettings.watermark_prefix + i + j;
        /*设置水印div倾斜显示*/
        mask_div.style.webkitTransform = "rotate(-" + defaultSettings.watermark_angle + "deg)";
        mask_div.style.MozTransform = "rotate(-" + defaultSettings.watermark_angle + "deg)";
        mask_div.style.msTransform = "rotate(-" + defaultSettings.watermark_angle + "deg)";
        mask_div.style.OTransform = "rotate(-" + defaultSettings.watermark_angle + "deg)";
        mask_div.style.transform = "rotate(-" + defaultSettings.watermark_angle + "deg)";
        mask_div.style.visibility = "";
        mask_div.style.position = "absolute";
        /*选不中*/
        mask_div.style.left = x + 'px';
        mask_div.style.top = y + 'px';
        mask_div.style.overflow = "hidden";
        mask_div.style.zIndex = "9999999";
        mask_div.style.opacity = defaultSettings.watermark_alpha;
        mask_div.style.fontSize = defaultSettings.watermark_fontsize;
        mask_div.style.fontFamily = defaultSettings.watermark_font;
        mask_div.style.color = defaultSettings.watermark_color;
        mask_div.style.textAlign = "center";
        mask_div.style.width = defaultSettings.watermark_width + 'px';
        mask_div.style.height = defaultSettings.watermark_height + 'px';
        mask_div.style.display = "block";
        mask_div.style['-ms-user-select'] = "none";
        /*设置水印相关属性end*/
        shadowRoot.appendChild(mask_div);
      }
    }

    // monitor 是否监控， true: 不可删除水印; false: 可删水印。
    const minotor = settings.monitor === undefined ? defaultSettings.monitor : settings.monitor;
    if (minotor) {
      watermarkDom.observe(watermark_hook_element, option);
      watermarkDom.observe(document.getElementById(defaultSettings.watermark_id).shadowRoot, option);
    }
  };

  /*移除水印*/
  var removeMark = function() {
    /*采用配置项替换默认值，作用类似jquery.extend*/
    if(arguments.length===1&&typeof arguments[0] ==="object" )
    {
      var src=arguments[0]||{};
      for(key in src)
      {
        if(src[key]&&defaultSettings[key]&&src[key]===defaultSettings[key])continue;
        /*veronic: resolution of watermark_angle=0 not in force*/
        else if(src[key] || src[key] === 0) defaultSettings[key]=src[key];
      }
    }

    /*移除水印*/
    var watermark_element = document.getElementById(defaultSettings.watermark_id);
    var _parentElement = watermark_element.parentNode;
    _parentElement.removeChild(watermark_element);
  };

  var globalSetting;
  /*初始化水印，添加load和resize事件*/
  watermark.init = function(settings) {
    globalSetting = settings;
    setTimeout(function (){
      loadMark(settings)
    });
    window.addEventListener('onload', function () {
      loadMark(settings);
    });
    window.addEventListener('resize', debounce(loadMark,settings,200))
  };

  /*手动加载水印*/
  watermark.load = function(settings){
    // console.log('load',settings)
    globalSetting = settings;
    loadMark(settings);
  };

  /*手动移除水印*/
  watermark.remove = function(){
    removeMark();
  };

  //监听dom是否被移除或者改变属性的回调函数
  var callback = function (records){
    // console.log('records',records)
    if (globalSetting && records.length === 1 && records[0].removedNodes.length >= 1) {
      var rNode = records[0].removedNodes;
      var wmId = globalSetting.watermark_id || defaultSettings.watermark_id;
      if(rNode[0].id == wmId){
        loadMark(globalSetting);
      }

    }
  };
  const MutationObserver = window.MutationObserver || window.WebKitMutationObserver || window.MozMutationObserver;
  var watermarkDom = new MutationObserver(callback);
  var option = {
    'childList': true,
    'attributes': true,
    'subtree': true,
  };

  return watermark;
}));
